Speedup and efficiency.

Parallel speedup and efficiency of the benchmark system of Sec. Performance as a function of the number of cores using the machine described in Fig 3. (a) Speedup with different numbers of cores compared to one core. Optimally one would like to have a speedup that behaves like the identity (black dashed line). (b) Efficiency is the speedup divided by the number of threads, i.e., how efficiently the available cores were used.